Such installations typically include a water source, a vessel of pressurized CO apparatus for mixing the CO.sub.2 with the water for making carbonated water, and exchangeable containers or vessels for the flavoured syrup supplied by the syrup manufacturer.
For the purpose of better understanding the object of the present invention, reference shall be made to FIG. 1, schematically illustrating a typical layout of installations of the kind referred to above.
Hence, the installation comprises a water source 10, a pressurized vessel containing carbon dioxide gas 12 and apparatus 14 for admixing and dissolving the CO.sub.2 gas 12 in the water from source 10. The installation further includes the necessary devices for mixing the carbonated water with the soft drink syrup contained in a syrup container 16. As schematically shown, the dispensing machine head generally denoted 20 is normally activated when filler arm 22 is moved as by cup 24. A solenoid 26 opens a shut-off valve 28 and simultaneously actuates a carbonated water pump 30 and syrup pump 32 thereby controlling the flow of carbonated water and syrup respectively, in pre-determined proportions. Normally the proportion between carbonated water and syrup is 5:1. The mixture regulated by water valve 34 and syrup valve 36 is then dispensed via dispenser 38 to spout 39. These installations, with minor changes, are widely used all over the world.
It has recently been desired, by the beverage producing companies leasing such installations, to incorporate means for completely disabling the installation once the supply of syrup is interrupted, for example, when the syrup reservoir 16 has been exhausted. Since the installation was leased for the supply of a beverage based on the syrup produced by such leasing company, it should not be used for dispensing carbonated water which could be then consumed on its own or to which syrup may be added externally. The installation should thus be operable only when the syrup reservoir has been refilled or replaced with the leasing company's syrup.
Several solutions have been proposed to solve the problem. One solution incorporates a level indicating device 40, placed in the syrup reservoir 16, operatively connected as symbolized by line 42, which operates solenoid 26 so as to disable the operation of the shut-off valve 28, namely, keeping it closed once the level of syrup has reached the bottom of the reservoir 16.
According to another proposition, a pressure sensitive element 44 is operatively connected from the syrup supply line 46 to the mixing head of the machine, downstream of the pump 32. The device 44 similarly disables operation of the shut-off valve 28 through solenoid 26 once pressure in the line 46 drops as a result of the syrup reservoir becoming empty.
These two proposals suffer from the same disadvantage, namely that changes must be applied to the installation, remotely and outside the machine head 20. In the first example an electric cable must be connected (42) to the head of the dispensing machine 20 on the one hand and to the syrup reservoir 16 on the other hand, the reservoir being remotely located therefrom. According to the second proposition the syrup pipeline must be interrupted so that the device 44 could be included therein.
It is thus the major object of the invention to provide means for controlling operation of the carbonated soft drinks dispenser, with minimum interference to the construction of the installation as a whole.
It is a further object of the invention that the component part of the installation included in the dispenser head can be easily replaced by a modified component achieving the desired result.
It is a still further object of the invention to modify the construction of the syrup dosing adjusting element, associated with the syrup control valve, which element would be the replacable component capable of achieving the goal of the present invention.